Russ DeSantis/The Star-LedgerCostco gas station on Hwy 66 in Ocean Township, Monmouth County had to close because of a power outage that affected much of the county. From left are station attendees Diane McLaughlin, Middletown, Michael Facchini, Tinton Falls, and Patrick Trainor, Wall Twp.

MONMOUTH/OCEAN COUNTIES — A power outage at a Jersey Central Power & Light sub-station this afternoon sparked a massive blackout that left more than 70,000 Monmouth County residents without power and snarled rush-hour traffic along several highways, officials said.

The malfunction occurred sometime between 4 and 5 p.m. at the JCP&L's Atlantic Sub-station in Colts Neck, according to N.J. State Police spokesman Sgt. Stephen Jones, causing a wide-ranging blackout that affected several municipalities in Monmouth and Ocean counties.

First Energy Corp. spokesman Spokesman Scott Surgeoner said an equipment failure in the sub-station’s power transmission system caused the outage at 4:40 p.m.

Initial reports from JCP&L had the power outage at 10,000 customers, but that number continued to increase through the evening.

Glenn Mason, the coordinator of the county’s office of emergency managementm, said power was largely restored around 9:30 p.m.

The outage may have affected more than 70,000 homes and businesses, knocking out power in nearly every municipality in Monmouth County, according to JCP&L’s company website.

Asbury Park, Belmar, Holmdel, Long Branch, Middletown, Neptune, Ocean Township and Red Bank were among the hardest hit, according to the web site, with at least 5,000 customers without power in each location.

JCP&LJCP&L's power outage map shows problems throughout Monmouth County this afternoon.

Jones said hospitals in Red Bank, Holmdel, Long Branch and Neptune were running on emergency generators today evening, and at least four hospitals were without air conditioning due to the massive outage.

The blackouts also caused several traffic tie-ups along Routes 35 and 36 in Monmouth County, according to Middletown Police. Lt. Robert Stefanski said the outage knocked out traffic signals along both highways, and Middletown police officers were directing traffic in several clogged intersections.

Stefanski said the traffic issues had caused a few minor accidents, but both he and Jones said no one had been seriously injured as of 7:30 p.m. last night.